Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC 232854,232874,232882,232883,232886 for bus_get_dma_tag()

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Remove IPW_LOCK_DECL and fix various LORs.

Approved by: rpaulo (mentor)

Overhaul monitor mode handling:
o replace DLT_IEEE802_11 support in net80211 with DLT_IEEE802_11_RADIO
and remove explicit bpf support from wireless drivers; drivers now
use ieee80211_radiotap_attach to setup shared data structures that
hold the radiotap header for each packet tx/rx
o remove rx timestamp from the rx path; it was used only by the tdma support
for debugging and was mostly useless due to it being 32-bits and mostly
unavailable
o track DLT_IEEE80211_RADIO bpf attachments and maintain per-vap and
per-com state when there are active taps
o track the number of monitor mode vaps
o use bpf tap and monitor mode vap state to decide when to collect radiotap
state and dispatch frames; drivers no longer explicitly directly check
bpf state or use bpf calls to tap frames
o handle radiotap state updates on channel change in net80211; drivers
should not do this (unless they bypass net80211 which is almost always
a mistake)
o update various drivers to be more consistent/correct in handling radiotap
o update ral to include TSF in radiotap'd frames
o add promisc mode callback to wi

Reviewed by: cbzimmer, rpaulo, thompsa

Create a taskqueue for each wireless interface which provides a serialised
sleepable context for net80211 driver callbacks. This removes the need for USB
and firmware based drivers to roll their own code to defer the chip programming
for state changes, scan requests, channel changes and mcast/promisc updates.
When a driver callback completes the hardware state is now guaranteed to have
been updated and is in sync with net80211 layer.

This nukes around 1300 lines of code from the wireless device drivers making
them more readable and less race prone.

The net80211 layer has been updated as follows
- all state/channel changes are serialised on the taskqueue.
- ieee80211_new_state() always queues and can now be called from any context
- scanning runs from a single taskq function and executes to completion. driver
callbacks are synchronous so the channel, phy mode and rx filters are
guaranteed to be set in hardware before probe request frames are
transmitted.

Help and contributions from Sam Leffler.

Reviewed by: sam

Multi-bss (aka vap) support for 802.11 devices.

Note this includes changes to all drivers and moves some device firmware
loading to use firmware(9) and a separate module (e.g. ral). Also there
no longer are separate wlan_scan* modules; this functionality is now
bundled into the wlan module.

Supported by: Hobnob and Marvell
Reviewed by: many
Obtained from: Atheros (some bits)

Update ipw to work with the new net80211 stack, plus other driver improvements.

- Add proper scanning support rather than letting the firmware grab the first
access point
- Overhaul state changes
- Use macros for locking and provide _locked() versions of some functions
- Increase debugging output
- Use a callout rather than the old watchdog interface
- Improve style, function names and defines
- Add WPA (TKIP) support

Based heavily on a patchset provided by Sam Leffler.

Cleanup and document the implementation of firmware(9) based on
a version that i posted earlier on the -current mailing list,
and subsequent feedback received.

The core of the change is just in sys/firmware.h and kern/subr_firmware.c,
while other files are just adaptation of the clients to the ABI change
(const-ification of some parameters and hiding of internal info,
so this is fully compatible at the binary level).

In detail:
- reduce the amount of information exported to clients in struct firmware,
and constify the pointer;

- internally, document and simplify the implementation of the various
functions, and make sure error conditions are dealt with properly.

The diffs are large, but the code is really straightforward now (i hope).

Note also that there is a subtle issue with the implementation of
firmware_register(): currently, as in the previous version, we just
store a reference to the 'imagename' argument, but we should rather
copy it because there is no guarantee that this is a static string.
I realised this while testing this code, but i prefer to fix it in
a later commit -- there is no regression with respect to the past.

Note, too, that the version in RELENG_6 has various bugs including
missing locks around the module release calls, mishandling of modules
loaded by /boot/loader, and so on, so an MFC is absolutely necessary
there. I was just postponing it until this cleanup to avoid doing
things twice.

MFC after: 1 week

Hold on to firmware images until the interface detaches since
firmware_get() will not work while resuming. Note that we can't
simply drop the FIRMWARE_UNLOAD flag, because that will result in
a firmware image that can never be unloaded by the user since the
firmware subsystem will hold a linker reference to it (it's not
clear that firmware_put() without FIRMWARE_UNLOAD ever does quite
what you'd want).

sync w/ iwi:
o fix locking
o use firmware(9)
o cosmetic

Stop embedding struct ifnet at the top of driver softcs. Instead the
struct ifnet or the layer 2 common structure it was embedded in have
been replaced with a struct ifnet pointer to be filled by a call to the
new function, if_alloc(). The layer 2 common structure is also allocated
via if_alloc() based on the interface type. It is hung off the new
struct ifnet member, if_l2com.

This change removes the size of these structures from the kernel ABI and
will allow us to better manage them as interfaces come and go.

Other changes of note:
- Struct arpcom is no longer referenced in normal interface code.
Instead the Ethernet address is accessed via the IFP2ENADDR() macro.
To enforce this ac_enaddr has been renamed to _ac_enaddr.
- The second argument to ether_ifattach is now always the mac address
from driver private storage rather than sometimes being ac_enaddr.

Reviewed by: sobomax, sam

Printing a warning once when trying to bring up interface before firmware load.

Obtained from: imp (if_iwi)
Reviewed by: damien

Initial import of ipw, iwi, ral and ural drivers:

ipw - Intel PRO/Wireless 2100
iwi - Intel PRO/Wireless 2200BG/2225BG/2915ABG
ral - Ralink Technology RT2500
ural - Ralink Technology RT2500USB

Approved by: silby (mentor)